We are characterizing post mortem neurochemical alterations in brains from victims of cocaine-related sudden death. Our hypothesis is that chronic cocaine abuse affects cortical and brainstem areas which integrate the normative functions of the autonomic centers in brain. Abnormal activity in these autonomic centers may, in addition to the direct cardiotoxic effects of cocaine, lead to the pathogenesis of cardiac arrhythmias, myocardial infarction, and sudden death. We are correlating our findings whenever possible with the patterns of cocaine abuse and drug levels in brain and blood at the time of death. To assist us in analyzing the large amount of autoradiographic data we are producing, we are collaborating with the Resource on construction of a Human Brain Atlas. These digital atlas will include outlines of the structures of interest to us and tools to edit those rapidly to fit them onto images of brains experimental cases.